This application relates to a method of using a non-contact machining method, such as electro-chemical machining (ECM) or electrolytic machining to form airfoil leading and trailing edges.
Airfoils are utilized in any number of applications. As an example, a gas turbine engine commonly has airfoils associated with a number of rotating blades and a number of static vanes. A number of methods of manufacture are utilized to form the airfoils.
Typically, an airfoil could be said to have a pressure side, a suction side, a leading edge and a trailing edge. Optimal edge shapes often include complex curves, such as spline, parabolas or ellipses.
One popular method of manufacturing airfoils is electro-chemical machining (ECM).
In a common ECM system, a conductive workpiece is machined to form the airfoil. A voltage is connected to the workpiece and to an electrode (cathode). The workpiece is in a chamber with an electrolytic fluid. Precision ECM systems use complex cathode shapes that are place in close proximity to the workpiece to create complex geometry. This technique is expensive and results in long lead time tooling.
Metal is removed from the workpiece and complex shapes may be formed. However, as mentioned above, the leading and trailing edges, and in particular, very small sized edges, challenge traditional precision ECM methods. These methods have not been as effective in forming the desired edges.